TWI299696B - Solid sheet material especially useful for circuit boards - Google Patents

Description

1299696 (1) Description of the invention (Description of the invention should be stated: the technical field, prior art, content, embodiments and drawings of the invention) Brief Description of the Invention The scope of the invention relates to the inclusion of thermoplastic polymers having low hygroscopicity And a solid sheet of high tensile modulus fibers, wherein the thermoplastic polymer is a matrix polymer; a substrate for a circuit board produced therefrom; and the aforementioned method. BACKGROUND Circuit boards are used in important commercial items in virtually all electronic devices. "Plates" or support elements of circuits, boards or other electronic devices, such as interposers in flip chip packages, are important components of such devices, and the properties of the materials used to fabricate such boards are for electronics or circuits. The function is quite important. As electronic components become more complex, the demand for materials used in boards has also increased. For example, for many applications, the board has a coefficient of expansion that matches the wafer on the board, and/or the board has a low dielectric constant, and a low loss factor is preferred (especially when the high frequency device is mounted on the board) On time). These three factors are often adversely affected by the moisture absorption of the board material, which can change the size of the board and/or change the dielectric constant and/or loss factor of the board itself, and/or cause bending. The simplest board for applications where the conditions are relatively low is typically made of a thermosetting resin such as an epoxy resin filled with a fiber reinforcement such as fiberglass. The glass fibers, usually in the form of woven fabric, are saturated with a liquid epoxy resin to form a "prepreg" which is cured in the form of a sheet. As the demand for the board increases, the higher modulus non-melting fibers such as aramid can replace the glass fibers. However, fibers such as polyaryl Siamine fibers and epoxy resins absorb a significant amount of moisture, so they sometimes become uncomfortable 1299696

Used together in relatively high-performance board applications. Therefore, there is a need for an improved board material. The present patent application 2000-334871 describes the preparation of a prepreg sheet by means of a "laminated" three-layer structure, wherein the intermediate layer can be a nonwoven sheet comprising synthetic organic fibers, and the two outer layers can comprise Polyarylamine or other non-melting fibers. From the manner in which the prepreg is described, the sheet appears to be porous. The present patent application 11-117184 describes the preparation of a prepreg-forming sheet by forming a nonwoven sheet from a polyarylamine and a liquid crystal polymer (L(5p) fiber, which is heated under pressure. To allow the LCP to flow, and then to add a thermosetting resin to form a prepreg. The reported density of the sheet actually produced is porous. 曰 Patent Application 9-21089 describes LCP nonwoven sheets (paper) The preparation is said to have low water absorption. Other fibers may also be present in the sheet. After heating under pressure to partially bond the sheets, the product is still clearly a paper-like material. 曰 Patent Application 11- 229290 illustrates the preparation of paper made from LCP and polyarylamide fibers which can be impregnated with epoxy resin and then cured. The resulting sheet can be used as a circuit board. / or melt or flow under pressure. SUMMARY OF THE INVENTION The present invention comprises: a sheet comprising: (a) a nonwoven sheet of high tensile modulus short fibers, and (b) a thermoplastic polymer having low hygroscopicity ; this sheet has its calculated density 1299696

(3) At least about 75% of the apparent density. A laminate made therefrom; a circuit board made therefrom; a method of making a solid sheet material comprising heating and applying pressure to a structure sufficient for: (a) a multilayer sheet structure, including At least one layer comprising a nonwoven sheet of high tensile modulus fibers and at least one other layer, and at least one of the layers comprising the thermoplastic polymer having low hygroscopicity; or ~ (b) single layer sheet The structure 'comprises a nonwoven comprising a short length of high tensile modulus fiber and a thermoplastic polymer having a low hygroscopicity; and forming a sheet having an apparent density of at least about 75% of its calculated density. Specific drumsticks are used in specific terms. Some of them are defined as follows. The term "thermoplastic polymer with low hygroscopicity" (TP) means that less than 1.0% by weight of moisture is absorbed when measured on a piece of pure thermoplastic polymer by the method described below (by weight of thermoplastic polymer) ) Thermoplastic plastic polymer. The hygroscopicity of the thermoplastic polymer is preferably about 0.5% by weight or less, more preferably about 0.25% by weight or less, and most preferably about 10,000 parts by weight or less. The term "high tensile modulus fiber" (HTMF) means that when measured by a twist multiplier according to the ASTM D885-85 method, these product forms have a tensile number of more than about 10 GPa. It is preferably about 50 GPa or more, more preferably about 70 GPa or more. HTMF here includes high tensile modulus fibers, fibrils (4) 1299696

And ^ dimension (7) ring, (4) special instructions do not include all three. HTMF, (9) organic material' and it does not include any kind of carbon fiber. The so-called "Μ" refers to the test of the TOT test in the TOT test as described in U.S. Patent No. 4,118,372 (the disclosure of which is incorporated herein by reference). By thermotropic it is meant that [CP can be melted and the melt is anisotropic, as illustrated in the TOT test. By "sheet containing or containing non-woven HTMF" or "containing or containing non-woven HTMF" fabric or "paper containing or containing non-woven HTMF" means a non-woven sheet containing (or including) short HTMF (or Fabric or paper). In this context, the terms "paper", "sheet" and "r fabric" are used interchangeably. By "non-woven sheet" it is meant herein any use of any number of different methods, such as wet laying (usually referred to as paper) wet laying, dry laying, flash spun, dazzling spinning , mechanical needle (mechanicaiiy needled felt), spunlaced formed of non-woven "fabric". The preferred form of one of the nonwoven sheets is as described in U.S. Patent Nos. 4,886,578 and 3,756,908, the entireties of each of which are incorporated herein by reference. Other HTMFs can also be used similarly. The method also includes the use of a binder as desired, wherein the binder includes, but is not limited to, polyarylamine microfibers and other binders known in the industry. U.S. Patent No. 3,620,903, the entire disclosure of which is incorporated herein by reference in its entirety in its entirety in its entirety in the the the the the the the the the the By "fiber" is meant an object having a length and a maximum cross-sectional dimension, typically in the range of from about 3 micrometers to about 1 micrometer, and the aspect ratio (length/width). 50. SSS -9- 1299696 (5) The so-called at least aryl conjugated fibers are aggregated to a maximum of about chlorinated so-called diameters, and the so-called maximum sized particles are here at 320 ° C. The inner-numbered group of pigments or all or more of them are called r ^ (four),

By "polyarylamine fiber" is meant herein an aromatic polyamide fiber having 85% of its indoleamine (-CONH-) linkage attached directly to the two aromatic rings. The polyamine may optionally contain additives, and the additives are dispersed throughout the polystructure, and it has been found that up to about 10 weight percent of the materials can be blended with the polyarylamine. It has also been found that a copolymer having a diamine substituted with 10% of other diamines for polyarylamine or a diamine substituted with 10% of other diacid chloride can be used. ~ "原灭维" means a fiber-like material having an aspect ratio of from about 3 microns to about 25 microns, from about 3 microns to about 100 microns. By "microfiber" is meant herein a very small, non-particulate, fibrous or film particle having at least one of its three dimensions relative to the size of the inch. These particles are prepared by precipitating a polymerization solution using a non-solvent under high shear. - The term "polyarylamined microfiber" as used herein means a non-particulate film-like particulate guanamine microfiber having an aromatic polyamine having a melting point or a decomposition point, typically having from about 0.2 mm to about 1 The average length of millimeters is about a length to diameter ratio of from about 5 to about 10. The thickness dimension is about one micron, such as from about 0.1 micron to about 1.0 micron. In addition to the arylamines, the polyaryl decylamine microfibers may optionally include a dye, such as a smear of other additives as described in U.S. Patent Nos. 5,965,072 and 5,998,309, each incorporated herein by reference. "Short fiber" or "short length" of a fiber herein means a fiber having an aspect ratio of less than -10- 1299696 (6) of about 2,000, preferably of about 200 to about 1000, and more preferably about 250 to about 600. By "powder" it is meant herein a material having an aspect ratio of less than three. These particles typically have a largest dimension of from about 5 microns to about 1000 microns. The powder particles may have a smooth or rough textured surface and may comprise fibrils attached to the "central core" segment. The term "visual density" refers to the calculation of the total volume of one of the following sheets. Measure the thickness (if the average is slightly uneven, the average value should be measured), the length and the width..., and multiply the equivalent value by the volume. The sheet was weighed in the air. This weight is then divided by the volume to obtain the apparent density. The porous sheet will have a lower apparent density than its calculated density. By "calculated density" is meant the density at which an object is assumed to have no voids or pores, which is calculated from the amount and density of individual materials in the object. For example, if an object is 60 weight percent of a material having a density of 1.4 and 40 weight percent of a material having a density of 1.6, the calculated density of the object will be: d = 1. 0 / [(0.6 / 1.4) + (0.4 /1.6)] = 1.47 This type of calculation is well known in the art. By "solid" it is meant herein that the material has an apparent density of at least about 75% of its calculated density. Here, "one", such as TP or HTMF, means more than one here. By "comprising" is meant herein the presence of the alleged item (material) and any other additional materials or compositions. A preferred "solid" or "bonded" sheet will now be described. The solid sheet is preferably formed of a plurality of layers (two or more layers) or a single layer structure.

1299696 (7)

A preferred single layer structure comprises a TP-containing nonwoven HTMF sheet or fabric. TP can exist in many ways. It may simply be a powder interspersed between the fibers of the polyaryl nonwoven sheet. The HTMF nonwoven sheet may comprise TP (especially LCP) fibers (in other words, the sheet is a mixture of rayon fibers and HTMF fibers). The HTMF sheet may comprise ΤΡ (especially LCP) pulp or a mixture of various forms such as powder, fiber and/or pulp. Both ΤΡ and HTMF are not preferred for LCP. That is, TP is a lower melting point LCP and HTMF is a higher melting point LCP. The "fibrous" LCP can be formed simply by wet pulping a block of LCP such as pellets. For example, the pellets are mixed with moisture and, if desired, mixed with one or more surfactants, and the mixture is subjected to relatively high shear mixing. Mix as applied shear. The pellets will decompose into LCP fibrous particles.

If the solid sheet is formed of a multilayer structure, at least one of the layers must include an woven HTMF sheet or fabric, and at least one layer must contain TP ("TP layer"). For example, if two layers are present, one layer may be an HTMF nonwoven sheet and the other layer may be a TP nonwoven sheet or a TP film. The HTMF nonwoven sheet may also comprise TP, and/or vice versa. There may be more than one layer of nonwoven HTMF sheet or fabric, and/or TP layer. Typically, the TP layer will be from about 20 to about 95 weight percent, based on the total weight of HTMF and TP in the multilayer structure, preferably from about 30 to about 95 weight percent, more preferably from about 40 to about 95 weight percent, and about 70 to about 90 weight percent is particularly preferred. For example, polyarylamide papers typically weigh from about 15 to about 200 grams per square meter. In the TP layer, TP may be present as a film, paper, staple fiber, fiber, microfiber, fibril, or powder, or any combination thereof. For example, by -12- 1299696

Solid LCP has a tendency to fibrillate when machined, so that when LCP is in the form of particles, a combination of the above forms can be used, a particle form can also be used, and does not conform to any of the above defined TPs of the particles. The amount of TP present in the single or multilayer structure must be sufficient to form a solid sheet product. The TP will substantially fill all voids between the HTMF of the HTMF nonwoven sheet, as well as any voids between other materials that may be present, such as fillers. Since non-woven HTMF sheets or fabrics, especially paper, typically have a void space of from about 10 to about 70 volume percent, a single or multi-layer structure to be incorporated into a solid sheet will typically have at least about 20 volume percent. TP, more typically from about 30 to about 95 volume percent. The percentage of voids in the TP nonwoven sheet can be easily calculated by measuring the apparent density thereof and using the measured (solid) density of TP. These calculations are known methods. Other materials such as fillers, antioxidants, pigments, and/or other polymers may also be present in the single layer or layers as long as the final sheet is a solid. The conditions for forming the first solid sheet (assuming sufficient TP in a single layer or a multilayer structure) are a combination of temperature (heating), pressure, and length of time between heating and application of pressure. In general, the higher the application temperature, the lower the pressure required and/or the shorter the time required. The higher the pressure, the lower the temperature required and/or the shorter the time required. The longer the enthalpy, the lower the temperature and/or pressure that may be required: the lower the force. However, in most cases it may be desirable to heat the TP to a temperature at least near its melting point. If too low a temperature, or too low a pressure, or too short a time, or any combination thereof, is used, TP does not flow sufficiently to form a solid sheet. In this case, the temperature should be increased and -13 - 1299696 _ (9) l^Sil / or pressure and / or increase time. The most important variable of the salt letter is temperature, especially when it is close to the melting point of TP. Typically, during the flow of TP (at elevated temperatures and/or pressures), HTMF is at least coated with TP and, in most cases, encapsulated by TP. While some of the "fibers" of HTMF in HTMF nonwoven sheets can be moved relative to each other, in densified single or multi-layer sheets, HTMF nonwoven sheet structures are still present. When heat and pressure are applied to form the first solid sheet, a full or partial vacuum may also be applied to the single or multi-layer structure to be dissolved in the material of the single or multi-layer structure' or physically present in the structure, as in Air or other gases between HTMF and TP particles are removed. For example, a single or multi-layer structure can be placed in a vacuum bag or vacuum chamber before heat and pressure are applied. The use of vacuum helps to remove gas from the structure and avoids trapping bubbles (voids) in the first solid sheet. With regard to any of the methods described herein for combining single or multi-layer structures, the use of vacuum is preferred. Various methods can be used to apply higher temperatures and pressures. A simple device is a vacuum bag to which heat and pressure can be applied. A press or autoclave can also be used. A particularly good method is hot roll or tropical calendering. The temperature, pressure, and time of treatment (joining) with a hot roll or belt can be controlled quite well, such as controlling the final thickness of the first sheet. Calendering is a well-known technique, see, for example, U.S. Patent No. 3,756,908, the disclosure of which is incorporated herein by reference. To help ensure "complete" bonding, it can be calendered in a vacuum. Bonding (application of heat and pressure) to a solid sheet can be carried out in one or more steps. For example, more than one pair of calenderings can be used to gradually smooth the sheet -14-

1299696 (10) Combines into a solid structure. Each step can also be performed individually. For example, the sheet portions are combined and then combined in a second individual step. The metal layer on one or both sides of the sheet may be applied in a single step process, or in any step of the multi-step process. For example, a pair of calender rolls or belts can be used to join the sheets, the metal sheets are applied to one or both surfaces of the sheet, and the bonding is accomplished in a second pair of calender rolls or another belt. The resulting sheet is preferably "balanced" in the plane of the sheet in the X-Y axis (sometimes referred to as the machine direction and the transverse direction). By balanced property is meant that the tensile modulus and/or coefficient of thermal expansion (CTE) in one direction (machine or cross-fiber) is no more than twice the tensile modulus and/or CTE in the vertical direction, Not more than about 20% is better, and not more than about 10% is particularly good. This is especially good when the TP contains an LCP, and is very good when the TP (only) is an LCP. Forming a sheet by melt-extruding a TP containing a short random length of HTMF (but not a non-woven sheet form)

I tends to have large differences in tensile modulus and CTE between the machine and the direction and the transverse direction, especially when TP is LCP. This is disadvantageous for use in circuits and other electronic board applications. Any TP having low hygroscopicity such as a perfluoro thermoplastic resin [for example, polytetrafluoroethylene; tetrafluoroethylene and hexafluoropropane, perfluoro(vinyl ether) such as perfluoro(methyl ethoxylated ether) can be used. Copolymer], or ethylene; poly(ether-ether-ketone); poly(ether-keto-ketone); and poly(ether-ketone); polyester such as poly(ethylene terephthalate), poly (2,6-phthalic acid ethylene glycol), and polyesters derived from bisphenol A and isophthalic acid/terephthalic acid; polycarbonate, especially those with higher temperature glass transition temperature; poly 4 -methylpentene; poly(arylsulfide); poly(ether-quinoneimine); poly(aryl ether); and LCP. Preferred TP is perfluoropolymerization

1299696 (9) Things, especially those mentioned above, and LCP are particularly good. Preferred properties of TP are non-defective hygroscopicity, high melting point, low dielectric constant, and low dielectric loss coefficient. LCP has an excellent combination of these properties. Useful LCPs include those described in U.S. Patents 3,991,013, 3,991,014, 4,011,199, 4,048,148, 4,075,262, 4,083,829, 4,118,372, 4,122,070, 4,130,545, 4,153,779, 4,159,365,4 161,470,4,169,933,4,184,996, 4,189,549, 4,219,461, 4,232,143, 4,232,144,4,245,082, 4,256,624, 4,269,965, 4,272,625, 4,370,466 4,684,712, 4,727,129, 4,727,131,4,728,714, 4,749,769, 4,762,907, 4,778,927, 4,816,555, 4,849,499, 4,851,496, 4,851,497, 4,857,626, 4,864,013, 4,868,278, 4,882,410, 4,923,947, 4,999,416, 5,015,721, 5,015,722, 5,025,082, 5,086 , 158, 5, 102, 935, 5, 110, 896, 5, 143, 956, and 5, 710, 237, the entire disclosure of each of which is incorporated herein by reference. The TP such as LCP has a melting point of preferably about 180 ° C or higher, more preferably about 250 ° C or more, more preferably about 300 ° C or more, and particularly preferably about 325 t or more. The melting point was determined using ASTM D3418-82 at a heating rate of 20 ° C /min. The peak of the melting endotherm is regarded as the melting point. Such higher melting point TP will allow the board to undergo high temperature processing, for example, with less likelihood of bending in reflow soldering. Low bending is an important characteristic of the board used in the board. Since LCP has very low hygroscopicity and LCP has very low permeability to moisture, it is also particularly useful in this application. Another preferred form of LCP is an aromatic polyester or an aromatic poly(ester-guanamine), especially an aromatic polyester. The term "aromatic" refers to a portion of the aromatic ring of all atoms in the main chain, or

1299696 02) Functional groups such as an ester, a guanamine, or an ether (the latter may be part of a monomer used) may be substituted with other groups such as an alkyl group. Some of the most advantageous aromatic vinegar LCP systems are found in U.S. Patent Nos. 5,11,896 and 5,71,237. More than one LCp composition may be present in the first sheet, but one is preferred. Useful HTMF includes poly(phenyl benzobisoxazole), poly(phenylene bromide), poly(phenylbenzobispyrimazole), poly(benzene) which are polyarylamines. Sulfur), LCP, and polyimine. When calculating the concentration of such fibers, the sum of the fibers present in these types, such as the sum of the polyarylamine and the poly(phenylenebisbisazolidine) fibers present, will be used. Preferred properties are high modulus, homochromatic and/or glass transition temperatures and low hygroscopicity. Polyarylamines are preferred HTMFs. Useful polyarylamines include poly(p-phenylene terephthalamide), poly(m-phenylene phthalamide), and poly(p-phenylene/4,4,oxygen) The preferred polyarylamines of aniline to phthalimin are poly(p-phenylene terephthalamide), poly(m-phenylene isophthalate) and poly(p-extension) Phenylphthalic acidamine is particularly preferred. A description of the formation of various types of polyarylamine (short) fibers, microfibers, and fibrils is disclosed in U.S. Patent Nos. 5,202,184, 4, 698, 267, 4, 729, 921, 3, 767, 756, and 3, 869, 430, each incorporated herein by reference. In this article. A description of the formation of a non-woven aryl amide sheet, especially a paper, is found in U.S. Patent Nos. 5,223, 094, and 5, the entire disclosure of each of which is incorporated herein by reference. More than one polyarylamine can be present in the first sheet. The apparent density of the solid sheet is preferably at least about 75% of its calculated density, more preferably at least about 80% of the calculated density, and at least about 9% by weight of the calculated density, which is calculated for density. At least about 95% better, and its -17-1299696

(13) The calculated density is at least about 98% better. When heat and pressure are applied to form a solid sheet, a metal layer, such as a copper (or other metal) foil, may be placed on the outer surface (one or both sides) of the single or multi-layer structure to be bonded, such that a metal surface is produced. Laminate. The metal layer is typically etched to create a circuit line. It is also possible to combine different single or multi-layer structures with or without metal layers. Solid sheets, usually also metal layers, can be used as support "boards" for the board. These boards can be formed using techniques known in the art, see 'for example' MW Jawitz, "Printed Circuit Board Handbook (Printed Circuit) Board Materials Handbook), McGraw-Hill Book Co., New York (1997). For example, it is known how to coat an LCP (in addition to the combination of heat and pressure as previously described) metal (in addition to using a metal foil), see, for example, U.S. Patent No. 5,209,819, the entire disclosure of which is incorporated herein by reference. The manner of citing is incorporated herein by reference in its entirety. PCT Application Serial No. 214, 827,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, Alternatively, a solid sheet having no metal layer may be formed first, and then the metal layer may be attached to a solid sheet or more than one laminated solid sheet. The metal layer can then be attached to the outer surface. The combination of metal sheets may be bonded together using heat and/or pressure, or an adhesive may be used. When determining the apparent density of a solid sheet, such as the presence of a metal layer within and/or over a solid sheet, to measure the apparent density, the metal layer can be removed prior to measuring the apparent density (eg, using acid etching) ), or the metal layer can be retained, and its thickness and (known) density are calculated and used

1299696 (14) Take into account. If more than one layer of solid sheet is present [e.g., separated by a metal layer], the average apparent density (total apparent density) of the solid sheet present is used as a reference for the apparent density. Circuit boards made of the above materials (including printed wiring boards and printed circuit boards) generally have low hygroscopicity, and/or good high temperature resistance, and/or a relatively low coefficient of thermal expansion, and/or low dielectric constant. And/or a low bend - an excellent combination of properties of the board. Once the substrate board is formed, it can be processed and processed by a general method to manufacture a circuit board. ~ A "densified" sheet comprising one or more layers can also be used as a wafer package substrate, a wafer carrier and a chip package interposer or used therein. The procedure for determining the equilibrium hygroscopicity at 85 ° C and 85% relative humidity: Five samples (5 X 5 cm) of the same sample dried to constant weight at 105 ° C were placed at 85 ° C and 85% relative humidity in the humidity chamber. The weight of the sample was measured daily thereafter. When the average weight gain for three consecutive days is less than 1% of the total weight increase, the sample is considered to be saturated, and the average suction is calculated by dividing the total weight increase by the original weight of the sample and multiplying the result by 100. Humidity (equal to total weight increase). EXAMPLES The following examples illustrate preferred embodiments of the invention of our invention. Our invention is not limited to these embodiments. In the examples, all LCPs used have hydroquinone/4,4, bisphenol/terephthalic acid/2 derived from Mobi ratio 50/50/70/30/320, except as indicated. A composition of the compound of Example 4 of U.S. Patent No. 5,110,896. -19- 1299696 (15) Further, in the examples herein, poly(inter)phenylisophthalamide (PMIT) microfibers are prepared as described in U.S. Patent No. 3,756,908, The entirety of this is incorporated herein by reference. Poly(p-phenylene terephthalamide) (PPTA) has a linear density of about 0.16 tex and a length of about 0.67 cm (sold by E. I. du Pont de Nemours and Company under the registered trademark KEVLAR 849). Poly(ethylene terephthalate) (PET) fiber used: 2·1 dpf, 6 mm long, by Ε·I·DuPont de Nemours & Co., Inc. (Wilmington, D*E, USA) is sold as Merge 106A75. Glass fiber used: E-glass fiber, 6.5 micron diameter and 6.4 mm long, 〇11 such as 1^&1^114(:〇.(〇61^6厂(:〇80217,1;3八) Manufactured and sold as 乂 189. The poly(phenylene ether) (PPE) resin used was purchased from General Electric Co. (Pittsfield, MA, USA) Model 63D. Polybenzoxazole fibers used: 1.5 Dpf, *ToyoboCo., Ltd. (Kita-ku, Osaka 530-8230, Japan) was manufactured under the registered trademark Zylon® (cut to a length of 6.4 mm). Example 1 The LCP used was derived from Moerby 50/ Example 9 of 50/85/15/320 of hydroquinone/4,4'-bisphenol/terephthalic acid/2,6-nonanedicarboxylic acid/4-hydroxybenzoic acid U.S. Patent 5,110,896 The composition of the LCP. The particulate LCP is milled in a Bantam® Micro Pulverizer (type CF) with liquid nitrogen by passing a melt blended mixture comprising LCP (70 weight percent) and polytetrafluoroacetic acid powder (30 weight percent) Γ Jν J β η- -20- until the granules pass through a mesh screen of about 1 〇

1299696 (16) Yes. The granules were reground in the same unit with additional liquid nitrogen until they passed through a 40 mesh screen. 2.00 g of the p-polyarylamide fiber was placed in a standard laboratory pulp mill (described in TAPPI Test Method T205 sp-95) with 2500 g of water and stirred for 3 minutes. In addition, 69.13 grams of an aqueous, non-dried meta-polyarylamine microfiber slurry (0.43% Shopper-Riegler with a consistency of 330 ml) and 2.25 grams of the above-mentioned particulate LCP and about 2000 grams of water were placed together. Mix in a 1-person laboratory mixer and stir for 1 minute. The two dispersions were poured together into a handsheet mold of approximately 21 X 21 cm and mixed with an additional approximately 5000 grams of water. The resulting slurry had the following weight percentages of solid material: m-polyarylamine melamine fiber 6.5%; p-polyaryl decyl lintel 43.5%; granule LCP 50% 〇 formed wet laid sheet. The sheet was placed between two sheets of blotter paper, the rolling pins were placed by hand, and dried at about 190 ° C in a manual sheet dryer. A 7.1 X 7.1 cm piece was cut from the dried sheet, and the aluminum foil treated with the release agent Mono-Coat® 327W (sold by Chem-Ti*end Inc.) was placed on both sides and placed in a flat press MTP-20. (Tetrahedron Associates, Inc. sales) between two brass covers each 1 mm thick. The sheet was compressed in a press under the following conditions: temperature 360 ° C, pressure 1.8 MPa 2 minutes; temperature 360 ° C, pressure 89 MPa 5 minutes; then while maintaining a constant pressure of 89 MPa, while using a water to cool the platen . finally

The (compressed) sheet of 1299696 (17) has a basis weight of 108.8 g/m 2 , a thickness of 81 · 3 μm, and an apparent density of 1.34 g/cm 3 . The sheet was calculated to have a density of about 88% of the "solid" density due to a calculated density of about 1.52 grams per cubic centimeter. Example 2 The final sheet (laminate) of Example 1 was placed between two sheets of copper foil (20 micrometers thick), and passed through the same press, and using the same compression as described in Example 1. The copper surface laminate was prepared by cyclic hot compression. The 'polymer portion (without copper foil) in the final copper laminate had a thickness of 78.7 microns and an apparent density of 1.38 grams per cubic centimeter, which was about 91% of the "solid" density. Example 3 The strand of LCP was cut into pellets on a 30.5 cm diameter Sprout-Waldron C-2976-A single rotary disc refiner with a plate, and a gap of about 25 micrometers was used in one pass. The feed rate of 60 g/min and the continuous addition of water to about 4 kg of water per 1 kg of pellets were refined. The resulting LCP pulp was refined in a Bantam® Mici*opulverizer (type CF) to pass through a 30 mesh screen. An aqueous slurry was prepared by mixing LCP pulp with poly(p-phenylene terephthalamide) lint. The slurry has the following percentage of solid material (as a percentage of total solids): LCP pulp 65%; poly(p-phenylphenylphthalamide) lint 35%. A continuous sheet was formed from the slurry on a paper machine equipped with a horizontal air permeable dryer, Rotonier (Rotoformer and Fourdrinier). The headbox has a consistency of about 0.01%, a forming speed of about 5 m/min, and an air temperature of about 338 °C in the drying section. Forming paper 1299696

(18) Between two metal rolls having a diameter of 86 cm at ambient temperature, each is calendered at a speed of about 7 m/min and a linear pressure of about 6500 Newtons/cm. The calendered material has a basis weight of about 72.5 grams per square meter and an apparent density of about 0,82 grams per cubic centimeter, which is equivalent to about 57% of the calculated density. The tensile modulus in the machine direction is 2.52 GPa and in the transverse direction is 1.65 GPa. Ten laminated sheets (51 x 51 cm each) were placed between two 17 micron thick copper foils and compressed in a flat press under the following conditions: 348 ° C - 2.6 MPa - Ι minutes > ; 348 ° C - 34 kPa - 1 min >> 348 ° C - 2.6 MPa - 1 min > > 149 ° C - 2.6 MPa, 1 min. The thickness of the final #1 top laminate was 541 541 mm, which corresponds to a polymeric material having a thickness of 〇 5 〇 7 mm (the balance being copper foil). Estimating the polymer material in the final copper laminate based on the basis weight of the 10 lamination material loaded in the press (725 g/m 2 ) and the thickness of the polymer material in the final laminate (0.507 mm) The apparent density is 1.43 g/m2, which is equivalent to about 99% of the calculated density. After etching the copper foil, the CTE in the plane was measured to be in the range of 丨卯(5) 〆 °C. Example £

The LCP strands were cut into pellets on a Sprout-Waldron C-2976-A single-rotor disc refiner with a 3〇·5 cm diameter plate. The 25 micron interplate gap was used in one pass, about 60 The feed rate of gram per minute is refined by continuously adding water in an amount of about 4 kg of water per kilogram of pellets. This Lcp pulp was further refined in a Bantam 8 MiCr 〇pulverizer (type CF) to pass a 100 mesh screen having the following solid materials through 6 聚 poly(p-phenylene terephthalamide). The slurry was prepared by mixing LCP pulp with lint. The resulting ratio (as a percentage of total solids): -23- 1299696 (v) Formation of wet laid sheets. The sheet was placed between two pieces of blotter paper, the rolling pin was placed by hand, and dried at about 190 ° C in a manual sheet dryer. The dried sheet had a basis weight of about 67.0 g/m2. Make another sheet with the exact same steps. The two sheets were placed together between two sheets of aluminum foil, with a release agent on the surface thereof (see Example 1), and compressed in a flat press under the following cycle: 266 ° C - 〇 · 21 MPa -2 minutes>>266°C-15.9 MPa-2 minutes》93 °C-15.9 MPa-2 minutes. The bonded sheet has an apparent density of about 12.28 grams per cubic meter, which corresponds to about 91% of the calculated density.

More than Example A would consist of 87 weight percent PPTA lint (2.25 denier per filament, 6.7 mm fixed length product) and 13 weight percent poly(metaphenylphenyl phthalamide) A polyarylamide paper having a basis weight of 31 g/m 2 and a density of 64 g/ml prepared by microfibers was pre-impregnated with a commercial multifunctional epoxy system L-1〇7〇 as in Example 2. 32 prepregs prepared by the above method were further laminated in a vacuum press between two Cu sheets (17 μm thick) under the following conditions: (4) maintained in vacuum for 1 hour (no external pressure or temperature). (8) Heating from the ambient temperature to the ^/min) under the pressure of ^^^. (c) maintained at 200 ° C and 6.9 MPa for 1 hour. (d) Under the pressure, the arm is turned to room temperature (water is cold). The polymer portion of the final laminate φ > p1 ^ 曰, 丨 77 in the content of each oxyresin is about 5 percent δ after etching the copper foil, and the polymerization of the I laminate of Meguro The quality of the part of the object. The CTE in the machine direction is about η, 0 scoops, 11.2 ppmrc, and ppm/°C in the transverse direction, and at 85 ° C and 85% humidity. < Hygroscopicity is about 2.1 wt%. Η , 27 ·

Claims (1)

129 Prospective Survey No. 19795 Boxing transfer case Chinese application for patent model "Replacement (93 years I2 month): . . . Bu. .... . ' q 1 : : !?' , V:-:· · ν: :; -:,·, l ; - :::; .-- jj ...*«*^一一—·叫..· 1. A sheet comprising: (a) a high tensile modulus short poly a non-woven fabric of amide fibers; and (b) a thermoplastic polymer having low hygroscopicity selected from the group consisting of perfluoropolymers and liquid crystal polymers; the sheet having at least 75% of its calculated density Apparent density. 2. A sheet according to item 1 of the patent application, wherein the apparent density is at least 90% of its calculated density. 3. The sheet of claim 2, wherein at least some of the high tensile modulus fibers are coated or encapsulated by the thermoplastic polymer. 4. The sheet of claim 1, wherein the thermoplastic polymer absorbs no more than 0.25 weight percent moisture. 5. A laminate comprising: a sheet according to item 1 of the patent application, and at least one metal layer in contact with one of the surfaces of the sheet. 6. A circuit board comprising a sheet according to item 1 of the scope of the patent application. 7. A method of making a solid first sheet material comprising the steps of heating and applying pressure to: (a) a multilayer sheet structure comprising at least one short polyaryl amide fiber comprising a high tensile modulus a non-woven layer, and at least one other layer comprising a low hygroscopic thermoplastic polymer selected from the group consisting of perfluoropolymers and liquid crystal polymers; forming an apparent density having a calculated density of at least 75% The first sheet. 8. The method of claim 7, wherein the apparent density is at least 90% of the calculated density.